Brush-holder for commutator mechanisms.



C. B. MESTON & H. l. FlNCH. BRUSH HOLDER FOR coMMuTAToR MEcHANlsMs.

APPLICATION FILED MAY I6, 1917.

Patented Aug. 13, 1918..

r for Commutator Mechanisms, -of which theA y UNITED .STATES PATENT'ormoni CHARLES R. MESTON AND HERBERT I. FINCH, OF ST. LOUIS, MISSOURI,ASSIGNORS TO THE EMERSON ELECTRIC MANUFACTURING COMPANY, OIIS'rST.VLOUIS,` MISSOURI, A.

CORPORATION OF MISSOURI.

`:BRUSH-HOLDIER. FOR COMMUTATOR MECHANISMS.

'To all wom t may concern.'

Be it known that we, CHARLES R. MEsToN and HERBERT I. FINCH, citizens ofthe United and useful Improvement in Brush-Holders following is afullclear, and exact de scription, such as will enable others skilled 1nthe art to which it appertans to make and use the same, reference beinghad to the accompanying drawings, forming part of this specification.

This -invention relates generally to elec'-A trical apparatus, andspecificallyv to an 1m-l proved construction of brush holder forcommutator machines.

The broad-object of our inventlon 1s to provide a commutator brushholder which.

contributes to economy both in manufacturing cost and in operating cost.

A more specific object'of our invention is to provide a brush holderwhich with the substitution of a minor part, may be used interchageablyon either side ofthe commu-1' tator wheel. y

.Another object isv to provide a brush 'holder construction which' maybe advantageously employed in D. C. machines| to prevent current lossesthrough the frame of the machine, and to secure at the same time theproper radiation of the heat from the brush and the brush box. v

A further object is to provide a brush holderfwhich permits the quickand easy removal 'and insertion of the `brushes from v either side ofthe brush box, which permits such as would be taken on line 3-3 of Fig.1; l

Fig. 4 is a' detail illustrating an arrange- Speccation of LettersPatent.

Application led'lfay 16, 1917. Serial No. 168,961.

Patented Aug. 13, 191s.

ment of the device for certain classes of A. C.machi1 1es. l v

' Referring to these illustrations by means of the reference numeralsapplied,'let"it be.

understood that, 1 represents a base member of insulating material whichmaybe of gen` 2, a lthreaded bushing 5 iscast in the base member 1,forming a seat for a screw 6. The base member -1 has a countersunkportion concentric with the bushing 5, from which.

countersunk portion extend countersunk slotways 7 extending radially ofthe bushing 5 in different directions. A connection llnk 8 is. adaptedto occupy the countersunk portion just referred to, and the radiallyextending arm of said link 8 is adapted to occup either one of thecountersunk slotways 7. he sc lew 6 carries a sleeve 9, at the outer iextremity. o f which isv mounted the pressure arm 10. Thls arm may bestamped from sheet metal-and shaped .to provide the hub portion 103,with 'peripheral shoulders or retain- 'lng members 10",' and the armportion 10" extending laterally from the hub portion 10 and terminatingin contact members 10".

vIt is preferable that the pressure member be bilaterally symmetrical soas to permit its lbeing reversed relative to the brush box.

The sleeve 9 and pressure member 10 are held on the screw 6 by the headof the latter and by a nut 11 which is threaded onto the screw. When thescrew is seated in the bushing' 5, the nut 11 operates also to retainthe connection link 8 in one ofthe slots 7. A torsional sprin 12 isvdisposed on the sleeve 9, one end t ereof being retained by pin 14 onthe base member 1, and the other end being adapted to coperateselectively with the shoulders or retaining members 1()b of the pressurearm, whereby to hold the arm under the desired spring pressure. Thepressure of the spring may be varied by adJust- 'ment of the end whichengages the retaining members 10b. With the parts thus arranged,

the pressure member is urged by the spring to move the brush 4, withwhich one of the contact members 10d makes contact, toward thecommutator, and thereby hold it for the proper electrical contacttherewith. The brush may be instantly removed by swinging back thepressure member 10, and lifting out the brush.

In order to use the brush holder interchangeably on both sides of thecommutator, it is necessary to provide two springs, the same beingsimilar in construction but differentially wound, that is, one woundwith a righthand helix and the other with a lefthand helix.

v Bushings 15 are cast in the base member -1, opening at the rearwardside thereof, and

said bushings thereby form screw seats into which proper screws may besetto attach the brush holder to the machine frame. A given brush holdermay be attached on either side of the commutator wheel as, by placing aproper spring upon sleeve 9 and arranging the respective ends of saidspring in proper position5 on pin 14 and shoulders 10b, the pressure armwill coperate with the brush at either side of the brush boxselectively, and the connection link 8 may be adjusted as between theslots 7 to the most advantageous position.

It will be seen, consequently, that this device affords a veryeconomical brush holder by virtue of the small number of parts which maybe employed in this construction and the fact that for the most partthey ma be formed as stampings or punchings rom sheet metal. Moreover,the fact that the same i device with the change of. but a minor part,

namely, a spring may be used either as a righthand or as a lefthandbrush holder obviates much manufacture and handling cost.

Furthermore, the device contributes to econl omy of operation by virtueof the fact that the brush is completely insulated from the machineframe, the insulating material of the base, in fact, forming one of thewalls of the brush box; Likewise, the arrangement of the pressure springprotects it from injury by current from the brush.

In addition to the pressure member 10 being adjustable to either side'of the brush box, the connection link 8 is also similarly adjustablefrom one slot to the other so that it may be disposed in the mostconvenient position for the attachment of the brush connection 13, andin either adjustment it is heldin definite position by the slot walls ofthe base member.

A brush holder of this description has the distinct operating advantageof permitting proper heat radiation from'ithe brush and brush boxwhileat the same time providing the proper insulation of said parts fromthe machine frame, as the comparatively thin metallic member 2 allowsthe rapid dissipation of heat from the brush into the air.

1n Eig. 4, we have shown a modification in Vwhich the device is intendedfor use in a machine in which the brushes are short-circuited through aframe part on which they are mounted, such as is desirable practice incertain alternating current machines. In this modification, the basemember 1 is formed as a portion of a ring member 3 which is arranged t0be mounted on the motor frame, and which functions as a short-circuitingmember between the brushes. It willbe understood that the companion|brush is mounted on 'a similar base member carried by the.

.the base member 1 forms one of the Walls Vfor retaining the brush'. Thesame form of brush holder, pivot screw, pressure arm and spring may beemployed on both of the base members 1, said parts Acorresponding tothose hereinbefore described. 'The connection link 8, however, may bedispensed with,

the brush connection, if desired, bein made directly to the base member1'-, or to t e ring member 3; or the member 13 may be dispensed with andthe brush connection may be secured solely through the pressure member10, and thepivot screw 6 or link 8 used' as a binding post for a leadconnection.

We are aware that the device is susceptible of various modifications andadaptations not herein specifically illustrated or described, butcomprehended nevertheless within the scope and spirit of the appendedclaims.

What we claim is:

1. A brush holder comprising'a base member of insulating material, abrush box mounted thereon and cooperating therewith to form a containerfor the brush, anadjustable pressure member pivotally mounted on thebase member to one side of the brush box, and separate means supportedon the insulating base for urging the pressure memher for coperationwith a brush retained by the box.

2. In a brush holder, the combination of a brush box, a pressure memberpivotally and adjustably mounted adjacent theretoand having brushengaging members extending in opposite directions for coperation witheither end of a brush in said box, and adjustable means for urging thepressure member for coperation with the brush. Y p

3. In a brush holder, the combination of a base member, a brush boxextending transversely thereof, a pivot mc'nber Seated in the basemember at one side of the box, a pressure member rotatably mounted onthe pivot member, said pressure member including form a container forthe brush, a pressure member pivotally and adjustably mounted on thebase member, and attaching means for the brush holder coperating withthe base member and insulated from the brush box and the pressuremember.

5. A brush holder comprising a base meml 'mining the selective locationsof'said link.

ber, a box Amounted thereon and coperating therewith to form a brushcontainer, a-

brush disposed within said container, a pivot screw mounted on said basemember,A a pressure member, means for 'mounting said pressure member onthe pivot screw wherey said ,member may be swung from one Iend of thebox to the other for en agement .with the rear end of the brush in tecontainer, a spring coiled about the piv'ot screw and ad- 'ustablycoperating with the pressure mem'- er to urge the same against thebrush, and a. connection member on the base member disposed forelectrical` connection brush. c l Y 6. A brush holder comprising a basemember, a brush box mounted thereon, and an adjustable pressure memberpivotally mountwith the `Aed on said base member and provided with apair of oppositely disposed brush engaging portions.

7. A brush holder comprising a base member, a brush box mounted thereonand adapted for the reception of a brush, and a connection linkadjustably secured to the base member and adjustable to selectivepositions for reception of electrical connections; said base memberincluding portions for deter- 8.111,1 a device of the `class described,a base','.a brush box carried thereby, and a spring-pressed memberpivotally mounted on the base to one side of the brush box and adaptedto be swung from one side of the base to the other so as to engage therear end of the brush positioned in said brush box.

`In testimony whereof we hereunto aiix oursignatures this 14th day ofMay, 1917.

' CHARLES R. MESTON.

HERBERT I. FINCH.4

